The quality of water is really bad, lack of inner current and thick layer of mud prevent valuable flora and fauna from creating an actual micro-cosmos.

内部循环和厚层泥土的缺乏导致动植物稀少，无法创造真正的微气候环境。

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Workers continued to scrape at a thick layer of mud over the ground floor.

工人们继续在一楼的厚厚一层烂泥中搜寻。

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The explosions were accompanied by heavy rain, leaving the island's roads coated in a thick layer of mud.

BBC: Ash rains down on Montserrat